Front matter 2 Model Selection Obtain the bore of the cylinder tube.  Refer to Graph (1) and (2). P = 75 PSI W Fig. (2) W = 90 lbs P = 75 PSI Fig. (3) W W = 100 lbs Fig. (1) P = 75 PSI (Example) (Example) Graph (2) Retracting Side Cylinder Force (Double acting cylinder) Graph (1) Extending Side Cylinder Force (Double acting cylinder) Example 1: If the minimum force of 85 lbf is necessary to keep the workpiece pressed as shown in Fig. (1), because this is the extending side, use Graph (1) to determine the load factor of 0.7 and the operating pressure of 75 PSI. Then, seek the point at which the cylinder force of 85 lbf intersects, and this will result in a bore size of 1.5 inches. Example 2: To move a load with a 90 lbf weight horizontally on a guide as shown in Fig. (2), because the load is the same for both the pushing and retracting sides, use Graph (2), which is the retracting side with a smaller force. Determine the load factor of 1, and the operating pressure of 75 PSI. Then, seek the point at which it intersects with the load weight of 90 lbs, and this will result in a bore size of 1.5 inches. Example 3: To pull a load with a 100 lbs weight vertically upward as shown in Fig. (3), use Graph (2) to determine the load factor of 0.5 and the operating pressure of 75 PSI. Then, seek the point at which it intersects with the load weight of 100 lbs, and this will result in a bore size of 2.0 inches. Step 1 0.1 1 10 100 Cylinder force (lbf) NCM044 25 150 125 100 75 50 Operating pressure (PSI) NCM075 NCM088 NCM106 NCM125 NCM150 NCM200 1.0 0.7 0.5 0.4 0.3 0.2 NCM056 0.1 1.0 10.0 100.0 Cylinder force (lbf) 25 150 125 100 75 50 Operating pressure (PSI) NCM075 NCM088 NCM106 NCM125 NCM150 NCM200 1.0 0.7 0.5 0.4 0.3 0.2 NCM056 NCM044 Load factor (n) Load factor (n)